[FEATURE] Bootstrap smoke-test repo with bare-runner CI

[c-vigo]

Description

Create the public repository vig-os/devcontainer-smoke-test, deploy a workspace from the current devcontainer template, and verify that the shipped ci.yml workflow runs successfully in a real GitHub Actions environment.

Problem Statement

The CI workflow shipped under assets/workspace/.github/workflows/ci.yml is never executed in a real GitHub Actions environment as part of any testing process. If an action pin breaks, a uv version incompatibility appears, or a runner environment changes, no test catches it until a downstream user hits the failure.

Proposed Solution

• Create public repo vig-os/devcontainer-smoke-test
• Deploy a fresh workspace via init-workspace.sh (with placeholder values resolved)
• Set up branch model (dev/main) with branch protection
• Verify the shipped ci.yml runs successfully (lint, test, security, dependency-review jobs pass)
• Add a repository_dispatch listener workflow (stub for later cross-repo wiring in a follow-up sub-issue)
• Add a README documenting the repo's purpose and relationship to the devcontainer project

Alternatives Considered

See parent issue #169 for full alternatives analysis.

Additional Context

This is sub-issue 1 of 4 for #169 (Phase 1). Can be worked in parallel with sub-issue 3 (RC publishing).

Dependency graph:

• This issue and sub-issue 3 (RC publishing) have no dependencies
• Sub-issue 2 (container CI variant) depends on this issue
• Sub-issue 4 (cross-repo dispatch) depends on all three

Impact

• Backward compatible. Creates new infrastructure only.
• Public repo = free GitHub Actions minutes.

Changelog Category

Added

Acceptance Criteria

• Public repo vig-os/devcontainer-smoke-test exists
• Workspace is deployed from the current template with placeholders resolved
• Branch model (dev/main) is set up
• ci.yml passes on a PR to dev (lint, test, security jobs)
• repository_dispatch listener workflow exists (stub)
• TDD compliance (see .cursor/rules/tdd.mdc)